Turn off power to the air conditioner at the thermostat and breaker
Remove the front panel or access cover
Locate the indoor evaporator coil
Vacuum loose dust and debris from the coil area with a soft brush attachment
Spray the coil with a no-rinse evaporator coil cleaner
Let the cleaner sit for the recommended time on the product label
Wipe accessible coil surfaces gently with a soft cloth
Clean the condensate drain pan and drain line opening
Reinstall the access cover or panel
Restore power to the unit
Replace or clean the air filter
Schedule professional cleaning if the coil is heavily soiled or difficult to access